1. Field of Invention
The invention relates to a sound volume-controllable communication apparatus capable of outputting signals as monitoring sounds simultaneously with the transmission and reception of the signals.
2. Description of Related Art
Conventional telephone sets equipped with an on-hook dial function are designed so that at the time of on-hook dialing, various signals transmitted to and received from an exchange to establish a connection to an external apparatus can be outputted as sounds from a speaker provided separately from a handset.
Such a telephone set enables a user to hear various signal tones transmitted to and received from an exchange, without picking up the handset, since during the on-hook dial mode, the telephone set outputs, as sounds from a separate speaker, various signals received from the exchange (for example, a dial tone for notifying that the system is ready for dialing, a ring-back tone for notifying that the designated external apparatus is being called, a busy tone for notifying that the designated external apparatus is busy, and the like) or various signals transmitted to the exchange (for example, selection signals, such as the DP signal or the DTMF signal, that are transmitted in accordance with dialing operation).
Among the various signals outputted as monitoring sounds by the telephone set during the on-hook dial mode, the signals received from an exchange should be output at such a sound volume that a user can distinguish different signal tones, because these signals indicate whether the system is ready for dialing, or whether a designated external apparatus is being called or is busy.
On the other hand, the selection signals tones transmitted from the telephone set to the exchange usually do not need to be heard or distinguished on the side of the telephone set. The outputting of the selection signal tones at a high volume can be offensive to the ear. Although the conventional telephone sets with the on-hook dial function normally allow a user to adjust the monitoring sound volume so as to reduce the volume of selection signal tones, the adjustment also reduces the volume of the ring-back tone, the busy tone and the like, thereby making it difficult to distinguish those signal tones.
As a device for adjusting the volume of monitoring sounds in a telephone set of this type, Japanese patent application laid-open No. Hei 4-95437 describes an on-hook dial monitor that maintains a low monitoring sound volume up to a predetermined number of digits being dialed and then increases the monitoring sound volume.
Although this technology achieves a lower volume for the dial tone than the volume for the ring-back tone and the like, the technology cannot appropriately reduce the volume of the selection signal tones. More specifically, the aforementioned on-hook dial monitor merely maintains a reduced monitoring sound volume up to a pre-stored number of dialing digits. Therefore, if the number of digits of a telephone number, or the like, being actually dialed is greater than the predetermined number of dialing digits, the monitoring sound volume is increased before the dialing of the number is completed, so that ear-offensive or rough sounds caused by the transmission of selection signals are produced.
In addition to the ear-offensive sounds, the production of selection signal tones as monitoring sounds after an intermediate stage of the dialing operation, may give a user unnecessary uncertainty as to whether the digits dialed without being accompanied by monitoring sounds, were properly transmitted. These problems may be eliminated by setting the aforementioned number of dialing digits to a greatest number of digits conceivable as a telephone number or the like. With this countermeasure, however, if the number of digits actually dialed is less than the predetermined number of dialing digits, the monitoring sound volume remains low for some time after the dialing is completed, resulting in another problem that the volume is too low to clearly hear the ring-back tone and the like. Therefore, the employment of the aforementioned on-hook dial monitor still finds it difficult to appropriately control the volume of selection signal tones.
Although the problems of the conventional art have been stated in conjunction with a telephone set with the on-hook dial function, these problems can also occur in substantially the same manner in various other communication apparatuses with a similar on-hook dial function, for example, facsimiles or various data communication apparatuses with such a function.
As is well known, the DTMF signal transmitted from a telephone set is used not only for establishing a connection to an external communication apparatus, but also for transmitting data to an external communication apparatus as in the case of transmission of a message to a radio pager. Such data transmission may also suffer from the aforementioned problems, provided that the DTMF signal is outputted as a monitoring sound.
Accordingly, it is an object of the invention to provide a sound volume-controllable communication apparatus capable of outputting monitoring sounds while transmitting and receiving signals and capable of eliminating ear-offensive sounds, particularly when transmitting a selection signal.
According to the invention, there is provided a sound volume-controllable communication apparatus including a sound outputting unit capable of outputting a signal as a monitoring sound simultaneously with the transmission and reception of the signal, and a signal transmitting unit that transmits a signal corresponding to a number designated. At the time of transmission of the signal by the signal transmitting unit, a sound volume control unit performs control such that the volume of a sound output from the sound outputting unit is set to a volume lower than the volume normally set.
In the sound volume-controllable communication apparatus, when the signal transmitting unit transmits a signal corresponding to a number designated, the sound volume control unit performs a volume reduction control such that the sound output by the sound outputting unit is reduced to a volume lower than a normal volume. Therefore, although the signal being transmitted by the signal transmitting unit may also be output as a monitoring sound, the volume of the monitoring sound is lower than the normal volume. Consequently, the sound volume-controllable communication apparatus of the invention prevents the production of an ear offensive monitoring sound at the time of transmission of a signal even if monitoring sound signals are output during the transmission and reception of the signals. The communication apparatus also eliminates the problem that monitoring sounds are too low to hear at the time of the reception of signals.
The signal transmitting unit may transmit a signal corresponding to a number key simultaneously with operation of the number key, or may also transmit a signal corresponding to a number pre-stored in a memory.
If the signal transmitting unit transmits a signal simultaneously with operation of a number key, then the following occurs. That is, since the time required between the start of operation of a number key and the completion thereof, varies depending on the number of digits of a number to be called and the user""s key operating pace, it is impossible to employ a structure in which the time required between the start of the operation of a number key and the completion thereof, is pre-calculated and the sound volume control unit performs control during the calculation.
The sound volume-controllable communication apparatus may further include a plurality of number keys operable by a user so as to designate a number, and a detector unit capable of detecting the operation of each number key. In this embodiment, every time the detector unit detects operation of any one of the number keys, the signal transmitting unit transmits a signal corresponding to a number assigned to the operated number key and at a time that can be determined on the basis of the operation of the number key. The sound volume control unit performs control by setting a volume lower than the volume normally set, in accordance with the time.
In this embodiment, the signal transmitting unit transmits a signal at a time that can be determined on the basis of the operation of the number key. The signal transmitting unit may be provided in various forms. For example, a device that starts transmitting a signal simultaneously with the start of the operation of a number key, and ends the transmission of the signal simultaneously with the completion of the operation of the number key; a device that starts transmitting a signal simultaneously with the initial operation of a number key, and ends the transmission at the elapse of a predetermined length of time following the start of transmission of the signal; a device that starts transmitting a signal at the elapse of a predetermined length of time following the initial operation of a number key, and ends the transmission at the elapse of a predetermined length of time following the initial start of transmission of the signal; and the like. Since each of these devices transmits a signal at a time that can be determined on the basis of the operation of a number key, any of these devices may be employed as the signal transmitting unit.
In this sound volume-controllable communication apparatus, the transmission of a signal by the signal transmitting unit and the volume reducing control by the sound volume control unit are simultaneously performed every time a number key is operated. Therefore, even if the time required between the initial operation of a number key and the completion thereof, varies depending on the user""s operating pace or the number of the digits of a number to be designated, the control by the sound volume control unit can be performed without failure. Consequently, the monitoring sound at the time of transmission of a signal is not ear-offensive. At the same time, the communication apparatus also eliminates the problem that monitoring sounds are too low to hear at the time of reception of signals.
If the signal transmitting unit transmits a signal corresponding to a number pre-stored in a memory, the control by the sound volume control unit can easily be performed at an appropriate time and for an appropriate period since the number of digits of the stored number is known and the signals corresponding to the number can be transmitted at a predetermined interval or rate.
Therefore, the sound volume-controllable communication apparatus may further include a storage unit that stores a number. In this embodiment, the signal transmitting unit transmits, at a predetermined time, a signal corresponding to the number stored in the storage unit, and the sound volume control unit performs control so as to set a volume lower than the volume normally set, in accordance with the predetermined time.
This embodiment prevents ear-offensive sounds at the time of transmission of a signal, and eliminates the problem that monitoring sounds are too low to hear at the time of signal reception.
The signal transmitting unit may be provided in various forms. For example, a device that temporarily stores into a memory a number designated by a user, displays the number on a display device to allow the user to check the number, and starts actual transmission of signals when the user operates a transmission start key; a device that temporarily stores into a memory a number designated by the user, and after the number is called by transmitting signals, re-transmits the same signals when a redial key is operated; a device that stores into a memory a number registered by a predetermined operation, and then transmits signals corresponding to the registered number when a predetermined one-touch key operation is performed; and the like. Since each of these devices transmits signals corresponding to a number pre-stored in the memory, any of these devices may be employed as the signal transmitting unit.